Immunological approaches are essential for analyses of the pathogenesis of HIV-1 and SIV, and for uncovering protective mechanisms. The immunology core will contain complementing components drawn from expertise available at ADARC, CU and RU. Each component will serve a broad range of investigators and funded grants. Each will provide methodologies that would be difficult to replicate in individual labs. The core director is Dr. Ralph Steinman, an experienced cellular immunologist. The core co- directors are Drs. Len Chess and John Moore. The additional directors of the core are Drs. Robert Winchester and Douglas Nixon. Dr, Ralph Steinman has many collaborations with the other members of the Immunology core and this will facilitate the coordination of core activities, and sustain the design and availability of new methods and services. The core will provide immunological services including antibody and CTL quantitation, epitope mapping, HLA typing and immunohistochemistry, and also support a number of new or emerging technologies such as the production of dendritic cells and the immortalization of T cells with herpesvirus saimiri. Dr. Leonard Chess will be in charge of Herpesvirus Saimiri (HVS) transformation of human CD8+ T cells. Dr. Robert Winchester will be in charge of MHC typing and T cell receptor (TCR) repertoire analysis. Drs. John Moore and Douglas Nixon will measure the HIV-1 specific immune response, with emphasis on antibodies [quantitation, neutralization, epitope mapping for both HIV-1 and SIV antibodies] and CTL [limiting dilution analysis for CTL precursor (CTLp) frequency determination and epitope mapping]. Dr. Ralph Steinman and colleagues at RU (Drs. Nina Bhardwaj and Melissa Pope) will be in charge of providing primary populations of human macrophages and dendritic cells (DCs) from blood buffy coats, and carrying out immunocytochemistry and in situ hybridization to localize HIV-1 and SIV in infected tissues. Regular meetings between core members, and outside users will ensure maximal usage of facilities and services. Members of the core will also participate in educational and outreach programs so that the immunological studies will be widely known.